There is a flood of depression-related info online, but still there are fairly common aspects of depression that only rarely get attention. One of those underexposed things is how (in some of us) depression can occasionally trigger a stream of confusing, unsettling Deja Vu experiences.
You don’t need to be depressed to get an incidental Deja Vu; everyone can have it once in a while. It may be a weird experience, but by itself it is not abnormal. Depression however sometimes seems to generate several such experiences in a row, within a short time. Let’s take a look into this.
To begin with, what exactly is a Deja Vu? In French, “Déjà Vu” means “already seen” or “seen before”.
The term was first used by the French researcher Émile Boirac in 1876 in the magazine Revue Philosophique, and came back more prominently in his 1918 book L’Avenir des Sciences Psychiques, or The Future of Psychology. That book is now of course completely outdated, but if you’re interested: the full English version (with a wrongly translated title) can be downloaded as a free E-book from Archive.org.
Basically, a Deja Vu is when a specific sight, sound, taste or smell suddenly evokes a vivid recollection of something you’ve experienced before: a memory that at the same time you know cannot be true, because you’ve not really experienced that thing before. You seem to remember quite clearly having been somewhere before, having done or said or felt something before, even though on a rational level you know this just cannot be right.
My old Facebook friend Sigmund Freud theorized a hundred years ago that such events might be caused by repressed desires or traumatic memories that people could no longer access as regular memory. He called it “paramnesia”. Modern psychiatrists are more inclined to think it has to do with some abnormal reaction in our parahippocampal gyrus: a part of our brain’s medial temporal lobe that appears to regulate what we feel as familiar and what we don’t.
Let me tell you about the Deja Vu stream I had a few days ago. I was sitting in a rather depressed state at my table when Deja Vus began to appear, one after another. I had some music on the radio and suddenly I recognized the song: I knew I knew it, had heard it before, and I even got back the same slightly sad feeling I’d had the first time when I heard it, long ago. It took a short while before I realized that this was a new song: one that I could never have heard in the past.
A waft of scent came in from the garden through the open window and suddenly reminded me of an elaborate dinner I once had: it was this grassy, aromatic thyme-or-oregano smell of when I sat with formally dressed strangers at a grand white-draped table with large bowls of high cuisine food. Something I never did, I can tell you.
A few minutes later, the wooden top of my table made me suddenly recall again how I once stood in a museum-like chamber, in some English country house perhaps, where all the walls had been completely paneled from top to bottom with this very same brown kind of wood. A place where I’d never actually been. More such involuntary associations kept coming for about twenty, thirty minutes. Then it stopped.
Not everyone who has serious depressions will get such Deja Vu moments in a row, but I know from others that similar experiences are not uncommon.
I have two theories about the relation between depression and Deja Vus.
A first one has to do with the fact that research has established that Deja Vu experiences occur significantly more often among people with temporal lobe epilepsy. They often get them right before a seizure.
This had me thinking: could it have something to do with damage caused by ECT, electroshock treatments? After all, ECT does induce epileptic fits – that’s how it works, actually. I myself never had any form of spontaneous epilepsy, but (like more serious depression patients) I did get many ECT treatments in the past. Would people who’ve had ECT treatments perhaps be much more susceptible to Deja Vu experiences? Unfortunately, as far as I know, no psychiatrist has ever researched this possible connection.
My second theory is about a direct relation between depression and Deja Vus. It has to do with the “broken filtering” mechanism that I’ve discussed here before (see my post Broken Filtering, over a year ago).
What is this filtering? A kind of pre-selection that normally, for everyone, is provided by our brain on an unconscious level. In real life, thousands of little things happen every minute all around us. Pre-filtering ensures that we’re not continuously and completely overwhelmed by a deluge of sensory events and impressions: only a selected, limited amount of them is allowed to enter our brain on a more conscious level.
In many of us, depression tends to break this filtering. This can go either way. Filtering can run out of control and become much too strong: we will start feeling very numb. Even important “outside events” will no longer enter our brain. We just sit apathetic, our head feeling like it’s filled with wool, without noticing what’s going on around us anymore.
Or, the other way around, due to depression our filtering can become much too weak: with the result we’re getting overwhelmed by more (and more intense) sensory experiences than we’re able to handle.
It’s the latter situation that may be important here. You probably know this effect of depression, where filtering doesn’t seem to work properly anymore. You open your curtains when you get up and the light hurts your eyes; normal household sounds begin to come in like an ongoing cacophony of pistol shots so unbearably loud you’re getting a headache and feel like driven to madness; simply touching the fabric of your couch with your hand already feels crude and painful; and so on.
Perhaps in such a situation, Deja Vus work as a kind of surrogate filtering mechanism: some kind of last line of self-defense by your overwhelmed brain. By randomly converting a few of all those incoming sights, sounds, tastes, smells into fake memories, they get redirected and you get a little refocused. From the meaningless cacophony all around you, in this way the brain reconstructs some arbitrary new meaning for you: a memory – even though it is a false memory – that you can temporarily focus on.
Maybe this is what such Deja Vus really are: small limited moments of confusion that actually help to prevent or at least to contain the utter, more complete, meaningless, overwhelming confusion.
You can take my theories for what they are: just some wild guesses. In the meantime I do think it’s a pity that psychiatrists have never bothered to really research the relation between serious depression and frequent Deja Vu occurrences. Hopefully they will get to it, some time.
• tip: Getting several Deja Vu experiences in a row can be unsettling. But it does not mean you’re going mad. Maybe it’s just a normal, perhaps even sensible reaction of your brain that helps you contain your general, depression-induced confusion.
If you find your Deja Vus disturbing, or if they don’t stop after a while, what will help is – as so often – concentration: using a little bit of the Mindful approach. Try to concentrate fully on your own body or on one simple thing that is happening right before your eyes, and the Deja Vus will go away.
• note: A good, readable seven-page introductory article on Deja Vus in general can be found at the HowStuffWorks site: How Déjà Vu Works. Written by Lee Ann Obringer, it covers the different kinds of Deja Vu, a little of the existing research, and some of the theories I had to leave out here. However, it does not go into the possible relations between depression and Deja Vus.